1. Field of the Invention
The present invention relates to a tape feeder, more particularly, to a tape feeder in which an impact caused by a pitch transfer of a tape is removed, electronic components do not protruded, the exact opening and closing of a shutter is performed. Simultaneously, in the tape feeder of the present invention, it is possible to move manually when installing the tape feeder.
2. Description of the Background Art
Conventionally, an electronic component mount device sucks and picks up electronic components installed to a part feeder by vacuum to a nozzle of a transfer head, transfers and mounts the electronic components to a printed circuit board. There are many kinds of part feeder such as a tape feeder, a tube feeder and a tray feeder etc. Among these, especially, the tape feeder has been widely used because it is easy to supply the electronic components in large quantities.
Conventionally, as shown in FIG. 1, the tape feeder comprises a main frame 10, a cover plate 20 installed to an upper portion of the main frame 10, a shutter plate 30 installed to an upper portion of the main frame 10, a pitch transfer unit 40 installed to a lower portion of the cover plate 20 and a pitch transfer means 50 connected to the pitch transfer unit 40 for driving the pitch transfer unit 40.
The cover plate 20 is installed to a front side of the main frame 10, the shutter plate 30 is reached in good condition to an upper portion of the cover plate 20 and a push member 31 is formed at a front lower portion of the cover plate 20.
The cover plate 20 can be slide with a state that the push member 31 is inserted to a slide groove 21 formed on its side. A cover tape exfoliation unit 22 is formed at a rear side of the push member 31 and the push member 31 pushes the electronic components, so that the separation of the electronic components can be prevented.
Also, a guide groove 32, an oblong hole type, is formed at a side of the shutter plate 30, plural guide pins 34 are installed movably to the inside of the guide groove 32 and an incision groove 36 for receiving a pitch transfer member 52 is formed at a side of the guide groove 32.
The pitch transfer unit 40 comprises a first sprocket wheel 40a for performing a pitch transfer of an enclosure tape (not shown), a second sprocket wheel 40b installed to a side of the first sprocket wheel 40a for rotating together with the first sprocket wheel 40a, a latch 42 installed to a side of the second sprocket wheel 40b for preventing from rotating reversely the second sprocket wheel 40b, a first lever 43 in which its end is connected fixedly to a center of the first and second sprocket wheels 40a and 40b for performing a pitch transfer of the first and second sprocket wheels 40a and 40b, a rotation shaft 44 installed rotatably to the other side of the first lever 43, a second lever 46 connected and installed together with the first lever 43 by the rotation of the shaft 44, a third lever 47 positioned on the same straight line of the second lever 46, an elastic member 48 for connecting together the secong and third levers 46 and 47, and an eccentric cam 49 installed at a side of the third lever 47.
A pin 49a is formed at an eccentric portion which is apart from the center of the eccentric cam 49 and an end of the third lever 47 is installed to the pin 49a, so that the third lever 47 is driven by the rotation of the cam 49.
Also, the pitch transfer means 50 being driven together with the pitch transfer unit 40 comprises a transfer lever 51 in which its end is connected to the rotation shaft 44, and a pitch transfer member 52 connected to a side of the transfer lever 51.
As described above, in the conventional tape feeder, when the eccentric cam 49 is rotated by a driving source (not shown), the third lever 47 connected to the pin 49a formed at a side of the eccentric cam 49 performs a straight-line motion.
The second lever 46 positioned on the same straight line of the third lever 47 performs elastically a straight-line motion by the elastic member 48 connected to a side of the third lever 47 and a side of the second lever 46.
When the pin 49a formed at a side of the eccentric cam 49 takes a half-turn, the eccentric cam 49 pulls the third lever 47, whereas when the eccentric cam 49 takes a turn, the pin 49a is returned at its original position, the eccentric cam 49 pushes the third lever 47.
The first lever 43 is pulled by the movement of the second lever 46 and at this time, the first sprocket wheel 40a is rotated by the first lever 43 by one pitch.
Also, the second sprocket wheel 40b combined together with the first sprocket wheel 40a is rotated by one pitch, the second sprocket wheel 40b does not rotate reversely by the latch 42, when the second sprocket wheel 40b is rotated regularly, the latch 42 slides against its outer surface.
On the other hand, when the second lever 46 is pulled by the third lever 47, the transfer lever 51 combined together with the second lever 46 to the rotation shaft 44 is also pulled and performs a straight-line movement.
By the transfer of the transfer lever 51, the pitch transfer member 52 pushes a side of the incision groove 36, so that the shutter plate 30 is transferred by one pitch.
When the eccentric cam 49 takes a turn completely, the first lever 43, the second lever 46 and the third lever 47 are returned to the original position by the pin 49a, since the first sprocket wheel 40a and the second sprocket wheel 40b are rotated with one direction by the first lever 43 and do not rotated reversely by the latch 42, so that the enclosure tape advances by one pitch.
As described above, there are several disadvantages that since in the conventional tape feeder, the transfer lever 51 and the pitch transfer member 52 are formed integrally, in the setting process of the enclosure tape received electronic components for supplying the electronic components, the enclosure tape can not be driven separately, so that a working position of the enclosure tape and the electronic components can not be maintained closely.
Accordingly, it is a primary object of the present invention to provide a tape feeder in which the first and second sprocket wheels and shutter can be driven separately by using an eccentric cam.
Another object of the present invention is to provide a tape feeder in which its entire construction is simple and it can be initiated by a simple operation of the manual lever when mounting the tape feeder.
In one aspect of the present invention, to achieve the above-described objects of the invention, there is provided a tape feeder for supplying plural electronic components arranged and mounted to a tape in turn comprising: a main frame; a shutter installed to an upper portion of the main frame for opening and closing a component discharge opening of the electronic components; first and second sprocket wheels installed to a lower portion of the shutter for moving the tape received the electronic components by a predetermined pitch; a rotating latch connected to the first and second sprocket wheels for rotating the first and second sprocket wheels; plural levers connected to a side of the rotating latch for driving the rotating latch; an eccentric cam having a taper formed at its side constructed rotatably for driving the rotating latch; a shutter lever constructed for performing the forward and backward movement of the shutter by the driving of the eccentric cam; and a manual lever for moving the tape by one pitch by a worker when an initial work is set to supply the electronic components.